DWR Cymru Welsh Water is advising its customers to remain vigilant about being contacted by bogus callers pretending to be from Welsh Water.
The company, which provides water sewerage services to around 1.4 million households and business across Wales is advising customers that all Welsh Water payments are taken over a secure automated payment line.
If customers are suspicious, they should ask the caller for their telephone number to call them back.
Customers can call Welsh Water on 0800 281 141 to confirm if the call is genuine and should report any suspicions to the police on 101.
Welsh Water’s Managing Director Customer Services, Julia Cherrett says: “We are aware of some incidents of bogus callers where the caller pretended to be from Dwr Cymru Welsh Water.
"If customers are unsure about the identity of a person claiming to be from Welsh Water, either at the door or on the telephone, they can ring Welsh Water to confirm the caller’s identity.
“Genuine employees will not mind waiting while these checks are carried out. We urge all customers to be vigilant and for people to advise those they may feel could be vulnerable.”